Glove sewing machine



March 8, 1966 J, PAV 3,238,903

GLOVE SEWING MACHINE Filed Feb. 12, 1963 10 Sheets-Sheet 2 INVENTOR.

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GLOVE SEWING MACHINE Filed Feb. 12, 1963 10 Sheets-Sheet 4 202 2 0 58 INVENTOR.

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GLOVE SEWING MACHINE Filed Feb. 12, 1963 10 Sheets-Sheet '7 IN VEN TOR.

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GLOVE SEWING MACHINE lO Sheets-Sheet 8 Filed Feb. 12 1963 INVENTOR.

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BY Josef Fav 185' i m ii March 8, 1966 J. PAv 323,903

GLOVE SEWING MACHINE Filed Feb. 12, 1963 10 Sheets-Sheet 10 IN V EN TOR.

S Pv w 2 4M United States Patent 3,233,903 GLOVE SEWHNG MACHKNE .loset Pa Gottwaldov, Czechoslovakia, assignor to Stiruieni podniku terrtiiniho strojirenstvi, Liherec,

Czechoslovakia Filed Feb. 12, 1963, Ser. No. 258,671 Claims priority, application Czechoslovakia, Feb. 14, 1962, 929/ 62 13 Claims. (Cl. 1112-16) This invention relates to sewing machines, and more particularly to a machine for sewing gloves and similar objects made of leather or other material diiiicult to pierce by a sewing needle.

High quality leather gloves heretofore were hand sewn. Only hand sewing has been considered capable of drawing threads through relatively small pierced openings in the leather, and to avoid frictional damage to the sewing thread during sewing which would limit the useful life of the glove. The productivity of a worker sewing gloves by hand is quite low.

An object of this invention is the provision of a sewing machine which produces seams in leather equal or superior in quality to seams produced by hand sewing, and does so at a rate unattainable in a manual operation.

Another object is the production of a single-thread seam.

An additional object is the avoidance of unduly large openings in the leather for passage of the sewing thread.

A further object is the prevention of damage to the sewing thread by excessive frictional, tension, or torsional stresses.

With these and other objects in view, the sewing machine of the invention employs a needle having one pointed end and an eye in the other blunt end, and moves the needle by synchronously driven mechanisms through material which is being fed through a sewing area defined by the supporting structure of the machine. The mechanisms include two releasable clamping means normally spaced from the sewing area in opposite directions transverse of the path of the material being sewn. The clamping means are individually rotatable by needle rotating means. The needle while clamped in one of the clamping means is engaged by piercing means which push the needle through the material.

Other features and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description of a preferred embodiment when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof, and wherein:

FIG. 1 shows a sewing machine of the invention in side elevation, some elements being broken away for a better showing of others;

FIG. 2 is a top plan view of the machine of FIG. 1, portions of the structure being broken away;

FIG. 3 is a perspective lateral view of the material feeding mechanism of the apparatus of FIG. 1, and of associated elements;

FIG. 4 shows a detail of the device of FIG. 3 and cooperating elements in a perspective rear view;

FIG. 5 shows another detail of the device of FIG. 3 on an enlarged scale together with its actuating mechanlsm;

FIGS. 6, 8, and 9 are perspective views of the sewing area proper of the machine of FIG. 1, and of machine elements operating at or immediately adjacent the sewing area;

FIGS. 7 and show the subject matter of FIGS. 6, 8, and 9 in top plan view, the FIGS. 6 to 10 being illustra- Patented Mar. 8, 1966 tive of different operational conditions of the machine;

FIG. 11 illustrates the mechanism for clamping and rotating the sewing needle, and for moving it toward and away from the sewing area while clamped, the view being in perspective from a point laterally of and above the front end of the machine;

FIG. 12 shows a detail of the apparatus of FIG. 11 on an enlarged scale, and partly in section;

FIG. 13 shows another detail of the apparatus of FIG. 11 on a greater scale;

FIG. 14 illustrates the general layout of the piercing mechanism and of its drive, the View being in side elevation;

FIG. 15 shows an enlarged detail of the mechanism of FIG. 14 in side-elevational section;

FIG. 16 is a plan view of a portion of the device of FIG. 15 on a slightly reduced scale;

FIG. 17 illustrates another portion of the device of FIG. 15 in top plan view, and partly in horizontal section;

FIG. 18 shows a portion of the device of FIG. 15 on a further enlarged scale;

FIG. 19 is an enlarged detail view of the drive mechanism of FIG. 14;

FIG. 20 shows the mechanism of FIG. 19 in partial front-elevational section on the line A-A;

FIG. 21 is a partial front elevational sectional view of a portion of the drive mechanism seen in FIG. 1;

FIG. 22 shows the stitch tightening mechanism of the machine of FIG. 1 in a view generally corresponding to that of FIG. 11;

FIG. 23 illustrates a portion of the apparatus of FIG. 22 on a greater scale;

FIG. 24 shows the thread end pulling mechanism of the sewing machine in a perspective view;

FIGS. 25, 26, and 27 are enlarged perspective detail views of the mechanism of FIG. 24;

FIG. 28 is a perspective view of portions of the needle rotating mechanism and of the blocking mechanism for holding the sewn material during piercing;

FIG. 29 shows an enlarged detail of FIG. 28;

FIG. 30 shows another enlarged detail of FIG. 28;

FIG. 31 is an axially sectional View of the device of FIG. 30; and

FIG. 32 is a fragmentary perspective view of a needle releasing mechanism.

The illustrated sewing machine of the invention consists of the following basic components:

(A) The stationary machine frame and associated supporting structure.

(B) The drive machnism.

(C) The feeding mechanism for the material being sewn.

(D) A thread gripper mechanism.

(E) A needle clamping mechanism.

(F) A needle rotating mechanism associated with the clamping mechanism.

(G) A clamp actuating mechanism.

(H) A manual needle release mechanism.

(1) A piercing mechanism.

(J) A blocking mechanism for securing the material during piercing.

(K) A stitch tightening mechanism.

(L) A thread end pulling mechanism.

(M) A loop forming mechanism.

The support structure and elements of the several mechanisms are visible in FIGS. 1 and 2, but a better understanding of the structural connection and of the cooperation of the mechanisms may be had from FIGS. 3 to 32 which illustrate individual mechanisms or elements thereof alone or in cooperation with elements of other mechanisms, and with the threaded needle employed for sewing two layers of glove leather to each other.

(A) Supporting structure Referring initially to FIG. 1, it is seen that all other parts of the sewing machine are mounted on or in a box-shaped elongated fiat base 1. The head 2 of the machine extends upward from the base 1 and has an open top for access to the mechanisms mounted therein. The open top of the head 2 is protected by a removable cover 3.

The rear portion of the base 1 adjacent the head 2 further carries an upright support 4 on which a bracket 10 is supported, and the central base portion holds a column 5 for a feed disk 31. A bracket 11 attached to the column 5 supports a circular platform 13 (FIG. 2). A slide 6 projects through an opening in the top of the base 1, and is mounted on the inside of the base 1 for sliding movement longitudinally of the base 1, as will presently become apparent. The slide 6 carries a rotatable pressure disk 58 and a fixed bracket 12.

The front end of the base 1 further carries an upright support 7. A bracket 8 on the central base portion is connected with the afore-mentioned circular platform 13. A pillow block 9 is mounted on the base 1 near the head 2.

Supporting elements mounted in the base 1 and not seen in FIG. 1 include a bracket 18 (FIG. 28) and a bracket 20 (FIG. 4).

A removable cover 14 on the head 2 gives access to the internal elements of the drive mechanism. The head furthermore carries a block 15, two elongated sleeves 16, and a supporting lug 17 better seen in FIG. 11. The underside of the cover 3, not visible in FIG. 1, is provided with an integral bearing sleeve 19 (FIG. 32).

(B) Drive mechanism The drive mechanism includes conventional elements (not shown) such as an electric motor, and is described hereinafter in detail only with respect to those elements which are either parts of the invention, or directly cooperate with the devices of this invention.

The input member for that portion of the drive mechanism which is contained within the head 2 is a V-belt pulley 22 (FIG. 2) integral with a coaxial handwheel 23. As shown in FIG. 21, the hub of a stationary sun gear 24 is keyed to the cover 14. Planet gears 30 are rotatable about respective axes fixed with respect to the pulley 22 and simultaneously mesh with the sun gear 24 and with a spur gear 25 keyed to the main drive shaft 26 of the sewing machine. The pulley 22 and handwheel 23 are axially secured on the shaft 26 by a collar 26' on the shaft 26 which abuts from the inside against the cover 14, and by a cap nut 29 threadedly fastened to the outer end of the shaft 26. The pulley 22 and handwheel 23 are freely rotatable on the shaft. A sleeve 28 keyed to the handwheel 23 and a bushing 27 keyed to the shaft 26 constitute the two coaxial faces of a sleeve hearing which permits such rotation.

(C) Feeding mechanism The several elements of the feeding mechanism are mainly seen in FIGS. 1 to 10. Referring initially to FIGS. 3 and 4, there is seen the feed disk 31 arranged for rotary cooperation with the pressure disk 58 in a common horizontal plane. The cylindrical faces of the flat, dish-shaped disks 31, 58 are knurled. The disk 31 is mounted on a tubular shaft 31 which is journaled in the column 5 and whose lower end carries a disk 32. A shaft 33 is coaxially rotatable in the shaft 31'. The lower end of the shaft 33 carries a pinion 34 and a cylindrical cam 36 formed with an axially inclined peripheral cam groove 37. A pin 21 supported in the bracket 20 engages the cam groove 37. The top of the shaft 33 has a thread gripper 60 mounted thereon.

A segment 35 pivoted on the base 1 in a non-illustrated manner meshes with the pinion 34. A rod 38 links the segment to a bellcrank lever 39 pivotally supported in the head 2 by a pivot pin 44. A link 40 connects the lever 39 to one arm of a two-armed rocket 41 pivoted on a stationary pin in the machine head 2. The other arm of the rocker 41 carries a cam follower roller 42 engaging a cam track of a cam disk 43 fixedly mounted on the main drive shaft 26.

The carn disk 43 also cooperates with a cam follower roller 46 on one arm of a bellcrank lever 47. The lever 47 which is supported on a pin 48 in the machine head 2 is connected to a bellcrank lever 50 by a pull rod 49. The lever 50 is pivoted on a pin 51 fixed to the base 1, and is connected to a segment 53 by means of a link 52. The segment 53 is pivotally mounted on the side 6 by means of a pin 54.

The segment 53 meshes with a pinion 55 fastened on a vertical shaft 56 which is axially secured in the slide 6 by means of a sleeve 57 in a manner best seen in FIG. 6, and partly in FIG. 28. A thread gripper 70 associated with the pressure disk 58 is fixedly attached to the upper end of the shaft 56. A cylindrical cam 59 is fastened to an intermediate portion of the shaft 56, and its obliquely inclined cam groove 61 is engaged by a pin 21' mounted on the slide 6. The pressure disk 58 is mounted on the sleeve 57 and free to rotate relative to the shaft 56.

Referring next to FIG. 28, it is seen that the slide 6 is fixedly mounted on two parallel horizontal bars 205, 206 the ends of which are slidably received in bores of the base 1. Horizontally reciprocating sliding movement of the slide 6 may be actuated by a pedal 193 and by a return spring 2117. The forked end of one arm of a lever 187 is engaged by a pin 189 on the slide 6. The other arm of the lever 187 which is pivoted on a shaft 181 carries a pin 190 which abuttingly engages a lever 191 connected to the pedal 193 by a pull rod 192. The pressure of the spring 207 is adjustable by means of a threaded abutment 208 accessible from the outside as seen in FIG. 1. The spring 207 urges the disk 58 against the feed disk 31. The spring pressure is preferably adjusted according to the thickness of the material clamped between the disks 31, 58, and can be overcome by depressing the pedal 193 for release or insertion of material between the disks 31, 58.

A spur gear 67 mounted on the main drive shaft 26 is seen in FIG. 5 to mesh with a gear 68 journaled in the head 2 in a manner not further illustrated. A pin 68' eccentrically projecting from the gear 68 engages a forked arm of a lever 69 pivotable on a pin 71 in the head 2. The other arm of the lever 69 is connected to a pivotally supported feed arm 63 by a pull rod 66 to actuate stepwise forward rotary movement of the disk 32 whereas backward rotation of the disk 32 is blocked by a blocking mechanism 65. The feed arm 63 may be manually pivoted by a handle 64.

(D) Gripper mechanism The thread gripper mechanism is mainly illustrated in FIGS. 1, 3, 6, 7, 8, 9, and 10. The gripper associated with the feed disk 31 is fixedly attached to the shaft 33 under a spring-loaded cap 72. Rotary movement of the cap 72 in one direction about the axis of the shaft 33 is actuated by abutting engagement with the gripper 60, and in the opposite direction by a nonillustrated return spring.

The analogous gripper associated with the pressure disk 58 is arranged on the shaft 56 under a spring loaded cap 73 whose movements are actuated in one direction by the gripper 70, and in the other direction by a return spring 224 (FIG. 7). A stationary cover 75 extends partly over the cap 72 (FIG. 6) and is attached to the bracket 11 by a screw 74. A finger 76 is adjustably secured to the bracket 12 by a screw 77 having a knurled head. The finger 76 extends above the spring loaded cap 73. An abutment 78 (FIG. 6) on the bracket 11 under the cover 75 limits the rotary movement of the cap 72 by an engagement with a cap portion 220. A similar abutment 79 on the bracket 12 limits movement of the cap 73. The finger 76 and the cover 75 have horizontally aligned apertures (FIGS. 8 and 10), and define the sewing area proper therebetween.

The bracket 12 carries three spring wire tensioning guides 199, 201, 202. The guide 199 is approximately hook shaped, and the guide 202 normally extends straight upward across the bight of the guide 199 to form therewith a resilient eye arranged adjacently outside the knurled rim of the disk 58. The guide 201 extends inward across the rim of the disk 58. A substantial identical complement of spring wire guides 199, 201, 202 is mounted on the bracket 11 adjacent the feed disk 31 in an analogous manner.

(E) Needle clamping mechanism The clamping mechanism for the needle 80 consists of two substantially identical devices arranged above the presser disk 58 and the feed disk 31 respectively, as partly seen in FIGS. 1 and 7 to 10, and shown in detail in FIGS. 11 and 12 together with its actuating mechanism.

The clamping device associated with the pressure disk 58 has a pair of clamping jaws 95, and the clamping device near the feed disk 31 has clamping jaws 85, as is evident from FIG. 11. The clamping device including the jaws 95 is shown on a larger scale in FIG. 12, and the other clamping device conforms to the showing of FIG. 12, and thus does not require separate description.

The clamping jaws 95 are hingedly connected by a pin 86 fastened on a support 90, and are urged toward the open position by a spring 87. They are moved toward the closed position by a vertically elongated actuating rod 88 the lower end of which forms an upwardly tapering wedge. The two faces of the wedge engage the jaws 95 in such a manner as to hold the jaws, and to close them when the rod 88 moves upward. Such movement is urged by a helical compression spring 89 which is coiled about the rod 88 and abuts against an internally threaded disk 82 on the rod 88 within the generally tubular support 90 in which the rod 88 is axially movably supported. The lower end of the support 90 is formed with an integral flange 93 having two diametrically opposed notches 93. A click stop 94 biased by a spring 198 tends to engage the notches 93' and thus to secure the support 90 in two angular positions spaced 180 apart. An eye 94' connects the click stop 94 to an actuating rod 129.

A gear rim 91 is fixedly mounted on the upper end portion of the support 90, and meshes with a gear wheel 92. The gear wheel 92 carries a one-way coupling 96. A bearing ball 83 is held axially centered at the upper end of the rod 88 by a sleeve 84 threadedly mounted on the rod 88 and threadedly holding a retaining ring 81 for the ball 83. As shown in FIG. 11, the tubular support 90 and the gear wheel 92 are rotatably mounted on a carriage 100. The tubular support 107 on which the clamping jaws 85 are arranged is similarly mounted on a carriage 110.

The carriage 100 is fastened on the front ends of two horizontal supporting rods 97 which are longitudinally slidable in the elongated sleeves 16. The rear ends of the rods 97 are connected by a yoke 98. The yoke is hingedly linked by connecting members 99 and 101 to a threearmed rocker 102 which is pivotally supported on a shaft 105 mounted in the head 2. Two arms 103 of the rocker 102 carry cam follower rollers 104 which travel along separate cam tracks of a multiple-track cam disc 106 keyed to the main drive shaft 26.

The carriage 110 is slidably mounted on the two sleeves 16 and is connected by means of a pull rod 108 with a lever 109. The lower arm of the lever 109 is formed with a terminal longitudinal recess 111 in which a slide 112 is movable. The slide is rotatably mounted on a 6 rocker 113 pivoted on the head 2 by means of the shaft 115. The rocker 113 is equipped with rollers 104 which travel on respective calm tracks of the cam disk 106.

(F) Needle rotating mechanism The mechanism which actuates rotation of the needles about a vertical axis While clamped in the jaws 85, is best seen in FIG. 28. The rotary movement of the cam disk 43 on the shaft 26 is transformed into reciprocating movement of two adjustable entraining hooks 123 by means of a lever 118 mounted on a shaft 119 and carrying a cam follower 117 which travels on an eccentric face 116 of the disk 43. The lever movement is transmitted to the hooks by a rod 121, a connector 122, and a sliding bar 120 movably supported in the block 15. The hooks 123 engage respective studs 124 on the input members of the oneway couplings 96, thus causing rotation of the jaws 85, 95 in one direction in steps of 180 when the drive shaft 26 rotates continuously.

The movements of the click stops 94 which secure the jaws in predetermined angular positions are derived in synchronization with the rotation of the supports 90, 107 from an eccentric cam disk 125 on the shaft 26, as is best seen from FIG. 11. The cam follower rollers 126 of a rocker 127 pivoted on a shaft 128 travel over the cam disk. An actuating rod 129 is hingedly connected to the rocker 127. Collars 114 on the rod abut against the eyes 94' to release the clock stops 94. The stops are urged toward their locking positions by the springs 198 (FIG. 12).

(G) Clamp actuating mechanism The motion transmitting train which .actuates the vertical reciprocating movement of the rods 88, and thereby opens and closes the clamps 85, 95, consists of the respective compression springs 89 associated with the rods, and a lever system mounted under the cover 3, as best seen in FIG. 11.

The lever system includes two levers 132, 133 pivoted on the head 2 by means of a common pin 134. Abutments 130, 131 on respective front arms of the levers abut against respective bearing balls 83 (FIGS, 12 and 32) on the rods 88. The respective rear arms of the levers 132, 133 are hingedly connected to elongated shackles 135 formed with longitudinally elongated apertures 136 in which slides 139 are movable. Compression springs 200 resiliently hold the slides 139 in a normal position.

The threaded ends of rods 137, 138 which longitudinally pass through the shackles into the recesses 136 engage tapped bores in the slides 139. The rod 137 is reciprocated during rotation of the drive shaft 26 by a motion transmitting train including the cam disk 125 fixedly fastened on the shaft 26, and a cam follower 141 mounted on a lever and traveling on the cam track 142 of the disk 125 (see also FIG. 20). The rod 138 is reciprocated during rotation of the cam disk 125 by the cooperation of a cam follower 141 traveling on another portion of the cam track 142, with a lever 144 pivoted on a shaft 145 to which the rod 138 is hingedly attached.

The resilient connection between the levers 132, 133 and the associated rods 137, 138 permits the needles 80 to be manually released from the jaws 85, 95.

(H) Manual needle release mechanism As seen in FIG. 32, a short shaft 146 is rotatably mounted in the bearing sleeve 19 on the cover 3. The shaft 146 is axially secured by two hingedly connected fingers 210 urged by a spring 209 into engagement with a circumferential groove in the shaft 146. A bar 147 radially projecting from the shaft 146 in opposite directions may be engaged with the abutments 130, 131 by the turning of a handle 148 attached to the shaft 146 outside the cover 3. As is evident from FIG. 32, clockwise rotation of the handle 148 causes the abutment 131 to engage the ball 83 on the rod 88 associated with the jaws 85, and

to open the jaws. The rotation of the bar 147 in a counterclockwise direction will similarly open the jaws in an obvious manner, not illustrated in FIG. 32.

(I) Piercing mechanism The mechanism which causes the needle 80 to pierce the double layer of material to be sewn together, and to pass the sewing thread 280 through the pierced material is mainly illustrated in FIGS. 8, 9, 10, and 14 to 18. The mechanism has two parts respectively mounted on the supports 4 and 7. The two parts are closely similar in structure and function, and are substantially symmetrically arranged with respect to a tangential plane common to the feed disk 31 and to the pressure disk 58 and passing through the sewing area. The description will therefore be initially limited to the part of the mechanism mounted on the forward support 7, and the initial portion of the description will be understood to be applicable in an analogous manner to the part mounted on the rear support 4, as generaily illustrated in FIG. 14.

A guide bar 163 is fixedly mounted on the support 7 and slidably passes through an opening (not shown) in a clamp 164 which is tightened about a straight tube 151 in which a bar is longitudinally slidable, as seen in more detail in FIG. 15. The bar 150 is vertically slotted, and the slot is engaged by a transverse pin 152 mounted in the tube 151 to guide the bar 150 and to limit its movement outward of the tube 151. A rod 153 attached to the bar 150 is coaxially arranged in the tube 151 and is enveloped by a helical compression spring 154 the ends of which abut against the rod 150 and against a threaded axially perforated plug 155 which closes the forward end of the tube 151. The rod 153 passes through the plug 155, and its outer end carries an abutment member 156 which projects laterally of tube 151 (FIG. 17) for engagement with a fixed stop 159.

A sleeve 157 at the rear end of the tube 151 is tightened by means of a wing screw 153 to adjustably fasten a pressure pin 160 to the tube 151. As evident from FIG, 18, the free end of the pin 160 is slidably guided in an opening of the bar 150 and horizontally slotted to conform with the flattened, blunt rear end of the needle 80. A vertical slot in the free rear end of the bar 150 accommodates a thread holding finger 162 which is a two-armed lever pivoted on the bar 150, and urged to move clockwise, as viewed in FIGS. 15 and 18, by a compression spring 162' acting on one arm of the finger 162, whereby the other arm is resiliently pressed against a thread held at the free end of the pusher bar 150. The clockwise movement of the finger 162 is limited by a stop 161 (FIG. 18). A wire finger 149 extends from the bar 150 toward the sewing area.

The reciprocating movements of the two tubes 151 are derived from a single eccentric cam track 172 in the cam disk 125 in a precisely synchronized manner, but out of phase with each other as is evident from FIG. 11. The actuating mechanisms include respective hinged links 165 connecting the clamps 164 to levers 167, 177 pivoted on shafts 168 in the head 2.

The lever 166 which is associated with the part of the piercing mechanism arranged above the feed disk 31 is connected to a rocker 170 by a pull rod 169. The rocker is mounted on the shaft 105 and carries a cam follower 222. The cam follower is held in engagement with the radially outer face of the cam track 172 in the disk 125 by a spring 173. Details of the cam disk 125 and of its cam tracks are seen in FIGS. 19 and 20.

The lever 167 associated with the portion of the piercing mechanism arranged above the pressure disk 58 is linked to a bell crank lever 175 by a rod 174. The bell crank lever is pivoted on the pin 115, and a cam follower supported on the lever engages the cam track 172 out of phase with the follower 222. A spring 176 ensures engagement of the cam follower with the radially outer face of the cam track.

The short lower arm of the lever 166 is forked, and a slide 177 is retained within the recess formed in the forked end. The slide is attached to a flat bar 178 which is slidably secured below the top of the base 1 in guide lugs 179. The forward end of the bar 178 carries on its underside a forwardly tapering wedge-shaped cam 180 the function of which will become presently apparent.

(J) Mechanism for blocking the pressure disk 58 The mechanism which prevents movement of the pressure disk 58 away from the disk 31 during piercing is best seen in FIGS. 28, 30, and 31.

An outer member 183 of a roller coupling 182 is mounted on the shaft 181. The member 183 engages a sleeve 184 mounted on an inner coupling member 185. The outer cylindrical face of the member 185 is in contact with rollers 186. The axial end of the member 185 remote from the outer member 183 is fixedly fastened to the afore-mentioned forked lever 187. A slide 188 arranged in the forked end of the lever 187 receives the pin 189 which is mounted on the slide 6 as mentioned hereinbefore. The other end of the lever 187 carries a pin 190 which engages the spring-loaded end of the lever 191. The lever is connected to the pedal 193 by the pull rod 192.

The sleeve 184 is fixedly connected with a lever 194 whose two arms respectively carry rollers 195, 196. A stud 203 mounted on the lever 194 serves as an attachment for a tension spring 197 fastened to the stationary support structure. The spring holds the roller 195 in engagement with the face of the cam 180, and holds the roller 196 in engagement with a cam face of the lever 191.

In the position illustrated, the cam 180 prevents engagement of the clutch 182 and blocking of movement of the slide 6. When the bar 178 moves away from the roller 194 and releases the same, the spring 197 engages the clutch and blocks movement of the lever 187, thereby arresting the pressure disk in its position adjacent the feed disk 31.

(K) Stitch tightening mechanism The mechanism which actuates the movements of a stitch tightening hook 248 (FIGS. 7 to 10) is shown in detail in FIGS. 22 and 23. The elongated movable support 211 on which the hook is mounted is suspended on the bracket 10 which in turn is carried by the upright support 4. The front end of the movable support 211 has a pin 212 mounted thereon. Two parallel lugs 213 pivoted on the pin 211 rotatably engage a pin 214 projecting from the bracket 10 in a manner not shown in FIGS. 22, 23 for the sake of clarity, but indicated in FIG. 1. The rear end of the support 211 is pivotally mounted on the crank pin of a crankshaft 215. In order to make the spatial relationship of the elements of the stitch tightening mechanism more obvious, the support 211 has partly been shown in phantom view in FIG. 22. The crankshaft 215 is journaled in the bracket 10.

A second crank arm 217 of the shaft 215 is hingedly attached to a bell crank lever 219 by means of a rod 218. The lever 219 is journaled on the aforementioned shaft 119, and a pin 221 on the free arm of the bell crank lever 219 normally laterally engages an arm of the lever 118 described above in connection with the needle rotating mechanism.

A tube 225 is rotatably mounted in the support 211. As best seen in FIG. 23, its front end carries a cross member 226. A short arm of the cross member carries an abutment 227, and the longer arm carries a stud 241 on which a wire spring 239 is coiled. A guide channel 228 having the shape of an axially slotted cylinder is fixedly attached to the tube 225. The guide channel 228 has an axis spaced from and parallel tothe axis of tube 225, and is conformingly engaged by an axially slidable member 229 connected by a radial pin 230 to one arm of a rocker lever 231. The rocker lever is rotatably 9 mounted on the shaft 128, and carries a cam follower 232 which is held in contact with the cam face 234 of the cam disk 43 by a helical tension spring 235 attached to the pin 230 and to a stud 233 fixed in the head 2.

A cylindrical bar 236 is rotatably mounted in the tube 225. Its front end carries a transverse U-channel member 237. A recess in the member 237 is engaged by the abutment 227. The major portion of the member 237 extends radially away from the end of the bar 236, and thence forward in an axial direction. A screw clamp 238 on the free end of the member 237 attaches the hook 240 to the member 237. The member 237 is urged into the position shown in FIG. 23 by the spring 239.

(L) Thread end pulling mechanism The mechanism for pulling the free end of the sewing thread 280 through the opening pierced by the needle 80 in the material to be sewn is best seen from joint consideration of FIGS. 1, 2, and 24 to 27.

A vertical shaft 250 is rotatably mounted in the bracket 8 which is fixedly attached to the base 1. The lower end of the shaft carries a pinion 251 (FIG. 24) which meshes with a segment 252 on a lever 253. The lever is pivotally attached to the base 1 by a pin 254, and is connected to a lever 256 by a link 255 and a universal joint. The lever 256 is pivotally supported on the pillow block 9 by means of a pin 257. The terminal portion 258 of a yoke 260 is attached to a forked arm of the lever 256 by a pin 259. Two spaced cam follower rollers 261 rotatably mounted on the yoke 260 are in simultaneous engagement with opposite surface portions of an eccentric cam 262 keyed to the main drive shaft 26. The yoke is slidably mounted in the cover 14. a

A T-shaped thread pulling arm 270 is attached by its base to the top of the shaft 250. Pins 2'73, 273' on the ends of the transverse portion of the arm pivotally secure spring loaded hooks 271, 272. The arm 270 projects above the circular platform 13 which is coaxial with the shaft 250, and which is fixedly mounted on the supports 4, '7, and the bracket 8. An upwardly open circumferential groove 281 on the platform has a raised discontinuous outer rim 282, and a beveled inner rim 283 (FIGS. 26, 27). A plurality of rollers 284 projecting above the platform 13 are distributed about the circumference of the platform, and are freely rotatable about respective vertical axes. Thin plates 285, 286, 287 having the approximate shapes of flat annular segments are arranged along the inner circumference of the groove 281. Their peripheral portions 289 are of reduced thickness. They partly overhang the edge of the groove 281, and define with the top surface of the platform 13 narrow horizontal slots 290 communicating with the groove 281, and extending therefrom in a radially inward directicn for receiving the thread pulled by the arm 270.

Elongated recesses in the top face of platform 13 partly receive torsion springs 288 arranged for catching and frictionally engaging a thread 280 moved through a slot 290 in a manner that will be described hereinbelow.

(M) Loop forming mechanism The mechanism for forming a loop in the thread adjacent the needle is partly seen in FIG. 11, but shown more clearly in FIG. 28, and partly in FIG. 29.

A pin 295 is vertically slidable in the supporting lug 17 which is fastened to the head 2. The pin is fixedly connected with two spacedly parallel vertical plates 296. A spring 299 urges the plates 296 to move downwardly away from the lug 17. Approximately horizontal parallel slots in the plates 296 guide the movements of two rollers 297 rotatably linked by a common shaft 298. The shaft constitutes the hinge pin which connects the members 99 and 101 in the afore-described needle-clamping mechanism. Integral lugs depending from the plates 296 are connected by a horizontal pin 301 from which a rod 302 is hingedly suspended. The lower end of the rod 302 '10 carries a movable earn 303 whose cam face is engaged by a cylinder 304. The cylinder is pressed against the face of the cam 303 by a spring-loaded wedge member 305 vertically slidable in the bracket 18.

A rocker lever 310 pivoted on the head 2 has an arm carrying an eyelet 307 through which the rod 302 passes. The rod is provided with a collar 308 adjacent the eyelet 307. A cam follower roller 42 on the rocket lever 310 travels on a cam face of the disc 43, and is urged against the cam face by a tension spring 311 mounted between the rocker lever and a stud 312 fixedly mounted in the base 1.

A pin 313 on the lower portion of the bracket 18 pivotally supports a bell crank lever 314 which is also shown separately in FIG. 29. The recess 319 in a forked arm of the bell crank lever 314 holds a sliding block 315. A pin 316 hingedly connects the block 315 with the wedge member 305. The other arm of the lever 314 is equipped with a threadedly adjustable abutment 317 which engages the rear end of a rod 318 whose front end is threadedly fastened to the slide 6.

The afore-described apparatus operates as follows:

The disks 31 and 58 are separated by depressing the pedal 193 and two layers of leather 300 which are to be joined by sewing are placed between the disks. The pedal is released and the material is clamped between the two disks by the force of the spring 207 which may be suitably adjusted by means of the threaded abutment 208.

The handle 148 is then turned counterclockwise, as viewed in FIG. 32, to press the abutment 130 of the lever 132 against the ball 83 atop the tubular support 90, thereby to open the clamping jaws 95. The needle is then placed between the jaws in such a manner that its thicker pointed front end is directed toward the aligned apertures of the finger 76 and of the cover 75 in the plane defined by the axes of the disks 31 and 58, and that the axis of the needle eye in the flattened rear end of the needle 80 is vertical. When the handle 148 is released, the needle is clamped in proper position between the jaws 95. A sufficient amount of threat 280 is then passed through the needle eye to make the length of the free thread end at least somewhat greater than the distance of the needle eye from the material to be sewn.

The machine drive is started, and the machine operates automatically thereafter. The needle 80 is carried by the horizontal movement of the clamping jaws toward the material to be sewn. The clamping of the needle by the jaws 95 is sufficiently firm to permit the pointed end of the needle to enter the material without slippage in the jaws. Even before the horizontal movement of the clamping jaws 95, the piercing mechanism is started. The rear end of the needle 80 is received in the front end of the bar 150, and engages the horizontal slot in the pressure pin 160, thereby being secured against rotation about the needle axis.

irnultaneous with the entry of the needle point into the sewn material, the grip of the clamping jaws 95 on the needle 80 is loosened by the lever 132 bearing down on the corresponding ball 83. The needle point which is guided in the aperture of the finger 76 and partly by the jaws 95 is further driven by the pressure pin 160. The bar participates in the movement of the pin until the abutment member 156 reaches the fixed stop 159. The pressure pin 160 then drives the needle 80 through the leather material 300 in the sewing area while the material is being firmly held between the disks 31 and 58.

The support 107 at this stage is located adjacent the aperture in the cover 75, and its jaws 85 are open for guiding passage of the front end of the needle as seen in FIG. 10. The jaws 85 are closed as soon as the necessary relative position of needle and jaws is reached, the pressure pin 160 is withdrawn, and the relatively thin rear end of the needle 80 and its thread 280 are pulled through the pierced material 300 by the jaws 85. When a short length of thread has been pulled through the sewn material, the direction of needle movement is briefiy reversed by the loop forming mechanism. The needle is then swung through an arc of 180 by the needle rotating mechanism, the material 300 is fed forward by the length of one stitch, and the needle 80 starts another piercing stroke in the manner outlined above. During piercing, the slide 6 is blocked by the clutch 182.

The formation of a loop from the thread between the needle eye and the sewn material 300 by a short reversal of needle movement is illustrated in FIG. 7. Immediately prior to initiation of the loop forming needle movement, the corresponding thread gripper 70 starts a rotary movement which engages the pointed front end of the gripper in the freshly formed loop, thereby separating the two runs of thread 280 in the loop.

When the needle reaches its terminal positions remote from the sewn material, the click stop 94 associated with the corresponding carriage 100 is lifted from a notch 93' by a collar 114 on the actuating rod 129, and the tubular support 90 is rotated in the same direction as the thread gripper 70, that is, clockwise as viewed in FIG. '7. The upper run of the aforementioned thread loop is thereby tensioned between the aperture in the finger 76 and the needle eye, whereas the lower run is taken along by the gripper 70 as shown in FIG. 8.

During its rotary movement, the rear end of the needle passes the spring loaded hook 271, partly shown in FIG. 8, and deflects it on its pin 273. While the rotation of the needle 80 is being completed, the thread pulling arm 270 swings the hook 271 about the axis of the shaft 250 away from the disk 58. The hook engages the lower run of the thread loop between the gripper 70 and the aperture in the finger 76, and thereby pulls the free thread end through the sewn material. Spring wire tensioning guides 199, 201, 202 are mounted on the bracket 12 in such a manner as to receive the loose thread end from the gripper 70 and the thread pulling arm 170, and to prevent its entanglement by moving parts when the gripper 70 returns toward its initial position as shown in FIG. 10, and when the end of the thread runs out of the hook 271.

When needle rotation is completed, the actuating rod 129 withdraws its collar 114 to permit the spring 198 to drop the click stop 94 into the notch 93' of the tubular support 90. The clamping jaws 95 thereby secure the needle 80 in the position shown in FIG. 9. The support 107 simultaneously performs a rotation through a semicircle to return to its needle receiving position.

The front end of the thread gripper 70 has a groove in which the lower run of the thread loop is initially received. During further gripper movement, the thread moves over a recess V toward the cylindrical back of the gripper from which it is forced through the obliquely inclined end of a narrow opening between the gripper 70 and the cap 73 as best seen in FIGS. 6 and 8. The thread then is guided in an arcuate slot in the cover 73 as best seen in FIG. 9, and a portion of the lower loop run is held in the path of the hook 271 above the cap 73 for pulling through the material 300 in the manner shown in FIG. 6. The portion of the lower loop run between the cap 73 and the aperture in the finger 76 is depressed by the cap 73 (FIG. 9) so as to be safely outside the range of operation of the stitch tightening hook 240.

The thread portion which originally forms the upper run of the loop between the needle eye and the aperture in the finger 76 is held tensioned by the guide 201 during rotation of the needle 80 about the vertical axis of the clamping jaws, and ultimately reaches a precisely defined position shown in FIG. 9 wherein the thread portion runs over a shoulder in one of the clamping jaws 95. The thread portion is ready for being engaged by the stitch tightening hook 240 as will be described hereinbelow.

During its rotary movement from the position shown in FIG. 7 to that illustrated in FIGS. 6 or 9, the gripper 70 and the cap 73 are raised in an axial direction by the interaction of the cam 59 and the pin 21' (FIG. 3). During the initial rotary movement, the gripper 70 and cap 73 move jointly, and thus hold the thread portion of the lower loop run in a circumferential position shown in FIG. 8. When the edge portion 220 of the cap makes contact with the abutment 79, the movement of the cap 73 under the pressure of the spring 224 is stopped while the gripper 7O continues its rotary movement, and a slot operated between the cap and the gripper to permit escape of the thread, and the thread is capable of being pulled through the recess V and over the raised edge of the pressure disk 58 by the hook 271.

The thread is pressed into the bight of the tensioning guide 199 in an early stage of gripper movement by abutment against the vertical wire pin 202 as best seen in FIGS. 6 and 9, and can only escape from the eye of the tensioning guide so formed by longitudinal movement against some frictional resistance.

The free thread end pulled by the arm 270 is guided to a torsion spring 288 (FIG. 26) in the slot 290 between the platform 13 and the plates 285 or 286 and 287 (see FIG. 2), and is trained over the rollers 284. During the pulling of the loose thread end by the arm 270, the piercing mechanism is actuated, and engagement of the needle by the bar prevents the rear end of the needle from being deflected in a lateral direction by the thread tension. The thread holding finger 162 also prevents the thread 280 from being pulled through the eye under the tension generated by the arm 270.

The stitch tightening hook 240 becomes effective immediately after the thread is secured by the finger 162. The hook is moved arcuately upward toward the position shown in FIG. 8 so that the upper run of the thread loop between the needle eye and the opening in the finger 76 is laid into the bight of the hook by the rotary movement of the needle 80. The hook then sequentially moves into the positions shown in FIGS. 8 and 9 and pulls the thread portion of the last-made stitch through the sewn material while the thread is being held by the finger 162 at the eye of the needle 80. The resilient force required to tighten the stitch without breaking the thread is provided by the spring 239 (FIGS. 22, 23).

While the needle 80 is being pushed through the material 300 by the pressure pin after the bar 150 is arrested by the fixed stop 159, the hook 240 pulls an amount of thread sufficient for the next stitch through the needle eye. During this thread metering operation, the thread 280 is held in the bight of the hook 240 by the wire finger 149 at the front end of the bar 150. The return movement of the bar 150 withdraws the finger 149, and the thread drops from the hook 240 while the hook is rapidly shifted to a position above the feed disk 31 to perform its function there when the needle 80 is moved in a direction from the feed disk 31 toward the pressure disk 58 in the next stitching step.

The return movement of the thread gripper 70 to its original position takes place while the sewing needle 80 is on the other side of the material 300, and the clamping jaws are briefly withdrawn to permit passage of the gripper, as shown for the gripper 60 and the clamping jaws 85 in FIG. 8.

While the several operations performed by the mechanisms of the sewing machine have been described with particular reference to movement of the needle from the area of the pressure disk 58 to that of the feed disk 31, it will be evident that the needle movement in an opposite direction takes place in an analogous manner, the two sets of operating implements of the sewing machine being arranged to a substantial extent in mirror image fashion.

The seams produced by the sewing machine of the invention are particularly attractive on leather gloves, but the invention is not limited to this application. The single-thread stitches are produced at a very high speed, and are indistinguishable from hand-made stitches except perhaps by their greater uniformity. The gloves produced on a sewing machine of this invention show high-quality sewing achieved at a high rate of output.

It should be understood, of course, that the foreg'oing disclosure relates to only a preferred embodiment of the invention, and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is:

1. In a sewing machine for gloves and the like, in combination:

(a) support means defining a sewing area;

(b) feeding means for feeding material to be sewn through said sewing area in a predetermined path;

(c) two releasable needle clamping means normally spaced from said sewing area on opposite sides of said path and on a line transverse thereto, said clamping means being movable for clamping and releasing a threaded needle;

(d) needle rotating means engageable with said clamping means for rotating the same;

(e) piercing means movable on said supporting means toward and away from a position of engagement with a needle clamped by said clamping means and for pushing the engaged needle through said material in said sewing area after release thereof by said clamping means; and

(f) drive means connected to said feeding means, said clamping means, said needle rotating means, and said piercing means for actuating the same in timed sequence.

2. In a machine as set forth in claim 1, loop forming means connected to said drive means and actuated thereby in said timed sequence for forming a loop in a thread held by said needle while said needle is being clamped by said clamping means.

3. In a machine as set forth in claim 2, thread pulling means engageable with a portion of said loop for moving said loop portion relative to said needle for tensioning the same, said thread pulling means being connected to said drive means for actuation thereby in said timed sequence.

4. In a machine as set forth in claim 3, said thread pulling means including a gripper member movable inward of said loop for dividing the same into two runs, a thread pulling member movable for tensioning one of said runs, and hook means movable for tensioning the other run.

5. In a machine as set forth in claim 1, clamp release means interposed between said clamping means and said drive means for tightening and releasing said clamping means in said timed sequence.

6. In a machine as set forth in claim 1, clamp reciprocating means for reciprocally moving said clamping means toward and away from said sewing area on said line, and connecting means operatively connecting said clamp reciprocating means to said drive means for actuation thereby in said timed sequence.

7. In a machine as set forth in claim 1, said feeding means including two substantially cylindrical disk members, yieldably resilient means for urging the substantially cylindrical faces of said disk members toward each other, and motion transmitting means connecting one of said disk members to said drive means for stepwise rotation thereby.

8. In a machine as set forth in claim 7, blocking means for blocking said disk members in a predetermined relative position while said needle is being pushed through said material by said piercing means, and connecting means operatively connecting said blocking means to said drive means for actuation thereby in said sequence.

9. In a machine as set forth in claim 1, manual means for releasing said clamping means.

10. In a machine as set forth in claim 1, an elongated needle adapted to be clamped by said clamping means and to be pushed through said material by said piercing means, said needle having two longitudinal end portions, one of said end portions being pointed and the other blunt, the blunt end portion being formed with a transverse passage to constitute an eye.

11. In a machine as set forth in claim 10, the cross sectional area of said pointed end portion being greater than the cross sectional area of said blunt end portion.

12. In a machine as set forth in claim 1, motion transmitting means interposed between said clamping means and said drive means for reciprocating said clamping means on said line.

13. In a machine as set forth in claim 12, said motion transmitting means including loop forming means for temporarily reversing the direction of movement of clamping means clamping a needle after said needle has been pushed through said material by said piercing means and clamped by said last mentioned clamping means.

References Cited by the Examiner UNITED STATES PATENTS 945,984 l/l9l0 Schomburg 223102 1,669,785 5/1928 Schmitt 1122 2,648,303 8/1953 Gerber 112-170 2,796,034 6/1957 Bihaly 112-2 X 2,844,113 7/1958 Wallenberg 112-l8 JORDAN FRANKLIN, Primary Examiner. M. I. COLITZ, Assistant Examiner. 

1. IN A SEWING MACHINE FOR GLOVES AND THE LIKE, IN COMBINATION: (A) SUPPORT MEANS DEFINING A SEWING AREA; (B) FEEDING MEANS FOR FEEDING MATERIAL TO BE SEWN THROUGH SAID SEWING AREA IN A PREDETERMINED PATH; (C) TWO RELEASABLE NEEDLE CLAMPING MEANS NORMALLY SPACED FROM SAID SEWING AREA ON OPPOSITE SIDES OF SAID PATH AND ON A LINE TRANSVERSE THERETO, SAID CLAMPING MEANS BEING MOVABLE FOR CLAMPING AND RELEASING A THREADED NEEDLE; (D) NEEDLE ROTATING MEANS ENGAGEABLE WITH SAID CLAMPING MEANS FOR ROTATING THE SAME; (E) PIERCING MEANS MOVABLE ON SAID SUPPORTING MEANS TOWARD AND AWAY FROM A POSITION OF ENGAGEMENT WITH A NEEDLE CLAMPED BY SAID CLAMPING MEANS AND FOR PUSHING THE ENGAGED NEEDLE THROUGH SAID MATERIAL IN SAID SEWING AREA AFTER RELEASE THEREOF BY SAID CLAMPING MEANS; AND (F) DRIVE MEANS CONNECTED TO SAID FEEDING MEANS, SAID CLAMPING MEANS, SAID NEEDLE ROTATING MEANS, AND SAID PIERCING MEANS FOR ACTUATING THE SAME IN TIMED SEQUENCE. 